Oracle Forms

i need to integrate forms with some java APIs. i used java importer to import the needed classes to my form.
i have two problems.
1- there is xml file beside the other jar files which is to be mapped. i think we can but .jar, .zip or .class files in class path but .xml is possible??? i but it but it does not work. so how to make it accessable?? in java dev i add it to the project and the it worked.
2- to raise th java exception i wrote the needed code but it mentioned that i need to import exception class. in java importer it said that java.lang.exception classnotfound. so way? isnt oracle platform contains java.lang? should i put the path of exception.calss in classpath?if yes what is the path?

thanks.